Method and apparatus for the laying of tunnel units below water



12, 1961 M. LASSEN-NIELSEN 3,012,406

METHOD AND APPARATUS FOR THE LAYING OF TUNNEL UNITS BELOW WATER Filed Nov. 25, 1958 United States Patent V 2, 7 METHOD. AND APPARATUS FOR THE LAYING F TUNNEL UNITS BELOW WATER Morten Lassen-Nielsen, Copenhagen, Denmark, assignmto Christiani'dz Nielsen A/S, Copenhagen, Denmark FiletlNov. 25, 1958, Ser. No. 776,253 2 Claims. (Cl.'-61'43) The invention relates to a method and apparatusfor the laying of tunnel units in extension of one another during the construction of a submerged tunnel.

In the construction of tunnels it is a known practice to proceed in the manner that the part of the tunnel to be built under a watercourse, a river or a large body of water is produced in theform of long or short, independent units built on shore, 'eigfin a drydock or on a slipway, and which after being launched andmade to float, either because'their weight'is less than their dis placement, or becausethey are suspended from. pontoons filled with air, are taken to their future location and lowered to the previously levelled bottom or to previously laid foundations. p

This method may involve considerable difiiculties, par ticularly in places where the tunnel is to lie in deep water or, where for other reasons it is difiicult to transport, manoeuvre or lower the tunnel unit from the surface, this work being to a great extent dependent upon the prevailing weather and current conditions, so that comprehensive measures must be taken to ensure that during the lowering the unit is kept in position so that it will come to rest in the desired place.

It is the object of the present invention to provide a method and apparatus which will make it possible to take such a tunnel unit to its place and lower it without having to work from the surfiace of the water and without the use of special floating cranes or other gear usually required for the lowering of the unit and Without use of the special moorings and bearing-taking apparatus otherwise required in great number for the purpose of keeping the unit in position before and during the lowering.

To achieve these objects in case of tunnels the units of which connected with the shore and situated in the shallow water close inshore are placed in the usual manner, the invention provides that the string of tunnel units already laid is used as a track for the units intended to be submerged in deep water.

For the performance in practice of this method, the tunnel units may on their upper surface be provided with longitudinal tracks, for instance railway tracks, along which the units may advance, and on their bottoms with wheels or rollers fitted to run on these tracks.

In order, in a particularly simple manner, to be able to undertake both the advance of a unit along the string of units already laid and the lowering of the unit at the free end of the string, the invention provides for the use of a crane to carry the unit along the string of units previously laid and so arranged that a tunnel unit suspended under it may be carried beyond the end of the string and, when the crane has advanced over the length of one unit, be lowered into place in extension of the string.

According to the invention such crane may expediently be designed as a gantry loosely enclosing the tunnel unit, through which gantry a new unit may be advanced along the tracks when the preceding unit has been released from the crane.

For the safe and reliable travel of the crane, it will also be expedient according to the invention to provide the tunnel units with crane tracks, preferably mounted on the outside of the sidewalls of the units, for instance on brackets mounted thereon, and to provide the crane with wheels or rollers fitted to run on the tracks.

3,012,406 Patented Dec. 12, 196i By proceeding in the manner described above :and with the use of the apparatusstated, long and deep-lying submerged tunnels may be produced very rapidly and without regard to climatic conditions, and the very considerable advantage will be derived'over the methods previously'known, that the tunnel unit in process of being laid may be firmly and accurately guided during the entire advance 1 and lowering operation in relation to the string of units previously laid, a feature which will greatly facilitate and accelerate the work as compared with the methods already known. 1

It may be observed thatthecrane required may be of a relatively slight construction when it is to be'used for the placing of tunnel units to be submerged, inasmuch as-their buoyancy in the water will reduce the load on the crane.

The invention is illustrated in the drawing in which FIG. 1 shows part of a string of tunnel units with a crane mounted thereon during the construction of a submerged tunnel, in side elevation,

FIG. 2 a section of the same with the parts in a different position, and

FIG. 3 a cross-section through tunnel and apparatus, viewed from the free end.

In the embodiment shown a tunnel is to be laid on the bottom 1 of a watercourse with surface 2. The tunnel consists of units 3 which are to be laid in extension of one another either on the levelled bottom 1 or, as shown in the drawing, on foundations 4 or other supports placed on the bottom. The performance of the method presupposes that the units of 'the tunnel situated on shore or in shallow water have been put into place in the usual manner, as the invention relates only to the units to be placed at such depths of Water as to provide suflicient space to allow their weight-'which may be very considerableto be lightened by buoyancy. For the advance of these units longitudinal tracks 5 are in the embodiment shown mounted on the tops of the units, which tracks, when the units are placed in extension of one another, will form continuous rails. The bottoms of the units are provided with wheels 6 corresponding to the tracks and preferably placed in such a manner that they will project as little as possible beyond the bottoms of the units 3. It will thereby be possible to bring the units forward to the end of the string of units already laid by running them along the tracks as indicated in the drawing in FIG. 1. In order to make it possible to lower a unit advanced in this manner into place off the free end of the string of units already laid, the embodiment shown provides for the use of a crane 7 formed as a gantry with wheels 8 corresponding to another set of longitudinal tracks 9 mounted on brackets 10 on the outside of the sidewalls of the units 3, so that a new unit advanced along the top of the units previously laid may be carried in through the opening in the gantry and placed in way of and be suspended from a winch 11 on the crane. The crane 7 may then, as indicated in FIGS. 1 and '2 travel forward along tracks 9, so that the unit is made to hang from winch 11 of the free end of the string and then be lowered down upon the foundations prepared for the purpose. In this connection it is of great importance for the use in practice of the method that the unit also during the last part of its travel is securely controlled by the crane and thus automatically will be brought to rest in the desired position. When the tunnel unit has been lowered and pulled up against the free end of the string, it will be released from 'winch 11 and joined to the rest of the string and may then serve as a track for the laying of the next tunnel unit in the same manner.

The invention may be performed in many ways other than those shown. In particular it may be pointed out that thewheels of the units and the tracks mounted on I I the units for the travelling of units and crane may-be formed in other ways. In this connection it is of importance to observe that even if the individual units may be' very' heavy, it will, due to the buoyancy, be possible to exert relatively light forcesand thus operate with comparatively slight gear.

' -I claim: 4 I

1.- A tunnel unit for installation under water with similar units by means of a wheeled crane to form a tunnel, each unit comprising a hollow, longitudinally extending block having a longitudinal through bore and having a flat top portion and side and bottom portions, said blocks being adapted to be arranged in successive,

ongitudinally extending, endwise abutting relationship to 7 form said tunnel, each said block having a longitudinally extending first tracks on its top portion and wheels on its bottom portion, said first tracks and said wheels being vertically aligned to permit one block to overlie a previously laid block with the wheels of the uppermost block longitudinally slidably received on the first tracks of the lowermost block, each said block having an outwardly extending bracket on each of the side portions thereof, and a second longitudinally extending track on the top of each said bracket, said second track being adapted to receive the wheels of said crane longitudinally slidably thereon.

2. Themethod of installing sub-aqueous tunnel units which have longitudinal bores in end-to-end abutting relationship, said method comprising forming first longitudinally extending tracks on the tops of said units, brackets on the sides of said units, and second'longitudinally extending tracks on the respective upper surfaces of said brackets and wheels on the bottoms "of said units, placing a first unit injposition in'the tunnel, moving -a hollow wheeled crane longitudinally over previously laid units by moving the crane wheels on the second tracks, drawing units subsequently to the first unit by their wheels over the first tracks of the previously laid units and through the hollow of the crane, and lowering the subsequent unit into end abutting relationship with the previous unit by means of said crane.

. References Cited in the file of this patent UNITED STATES PATENTS I 1938,265 ,Moir Oct. 26, 1909 1,345,175 Hall June 29, 1920 1,647,448 Jones Nov. 1, 1927 2,458,050 Blondelle Jan. 4, 1949 2,789,668 Apr. 23, 1957 FOREIGN PATENTS France 1949 

